ML24022A158

From kanterella
Jump to navigation Jump to search
(Vcsns), Unit 1 - Reply to a Notice of Violation: EA-23-093
ML24022A158
Person / Time
Site: Summer South Carolina Electric & Gas Company icon.png
Issue date: 01/22/2024
From: Carr E
Dominion Energy South Carolina
To:
Office of Nuclear Reactor Regulation, Document Control Desk, NRC/RGN-II
References
24-022, EA-23-093, IR 2023001
Download: ML24022A158 (1)


Text

Dominion Energy South Carolina, Inc.

5000 Dominion Boulevard, Glen Allen, VA 23060 Dominion Energy.com Document Control Desk January 22, 2024 U.S. Nuclear Regulatory Commission Washington, DC 20555 DOMINION ENERGY SOUTH CAROLINA (DESC)

VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 REPLY TO A NOTICE OF VIOLATION: EA-23-093 Serial No.:

VCS-LIC/JB:

Docket No.:

License No.: 24-022 RO 50-395 NPF-12 By letter dated December 21, 2023 (Reference 1 ), the Nuclear Regulatory Commission (NRC) notified Dominion Energy South Carolina (DESC) of a Notice of Violation (NOV 05000395/2023002-01) and associated White Finding.

The purpose of this letter is to provide the required written response to NOV 05000395/2023002-001, pursuant to 10 CFR 2.201. Attachment 1 provides the reason for the violation, corrective steps taken and results achieved, corrective steps that will be taken and the date when full compliance was achieved.

Should you have any questions regarding this response or require additional information, please contact Mr. Michael Moore, Manager Nuclear Emergency Preparedness and Station Licensing at (803) 345-4752.

Sincerely, Eric S. Carr President -Nuclear Operations and Chief Nuclear Officer ft Dominion ;t: a,, Energy

References:

Serial No. 24--022 Docket No. 50-395 Page 2 of 2

1. Letter from Laura A. Dudes (NRC) to Eric S. Carr (DESC), "Virgil C. Summer-Final Significance Determination of a White Finding and Notice of Violation and Assessment Follow-up Letter; NRC Inspection Report 05000395/2023091," dated December 21, 2023. (ADAMS Accession No. ML23342A000)

Attachment:

1. Reply to a Notice of Violation; EA-23-093 Commitments contained in this letter: None cc: G. J. Lindamood -Santee Cooper L Dudes -NRC Region II D. Dumbacher -NRC Region II G. E. Miller -NRC Project Mgr.

NRC Resident Inspector REPLY TO A NOTICE OF VIOLATION: EA-23-093 Dominion Energy South Carolina Virgil C. Summer Nuclear Station Unit 1 Serial No.24-022 Page 1 of 3 REPLY TO A NOTICE OF VIOLATION; EA-23-093 Reason for the Violation Serial No.24-022 Page 2 of 3 VCSNS failed to identify and correct a condition adverse to quality affecting its Emergency Diesel Generator (EOG) fuel oil system piping on both the 'A' and 'B' EDGs. This condition adverse to quality resulted in the failure of the 'A' EOG fuel oil piping, during testing on November 2, 2022.

Evaluation determined that the failure occurred at a threaded Schedule 40 piping connection.

A root cause evaluation determined that the cause for VCSNS failure to identify and correct the condition adverse to quality was the corrective action program governed by VCSNS procedure SAP-999 (Corrective Action Program). Specifically, Revision 13 and subsequent revisions of SAP-999 failed to drive effective evaluation/ resolution of the EOG fuel oil piping vulne rability.

Corrective Steps That Have Been Taken and the Results Achieved SAP-999 has been canceled and replaced with PI-AA-200, Corrective Action, which screens equipment deficiencies as conditions adverse to quality and drives effective evaluation/resolution. Additional corrective actions to address extent of condition and extent of cause are being implemented as determined by the root cause evaluation.

The affected EOG fuel oil piping has been replaced and bridging strategies, such as pre-staging replacement fuel oil piping and workorders, have been established for the EOG fuel oil piping until a design modification, scheduled for the first quarter of 2024, is implemented.

Corrective Steps That Will be Taken PI-AA-200, Corrective Action, will be revised to incorporate lessons learned from the root cause evaluation. VCSNS is implementing a Culture of Prevention model to focus on consequence bias and improve risk behaviors. Leade rship training is being provided as a part of implementation. Effectiveness reviews of the root cause actions will be performed to ensure the desired results are achieved.

The EOG fuel oil system is being re-designed and a modification is planned for implementation during the first quarter of 2024. This modifi cation will use heavier wall piping and additional pipe supports based on re-analysis of the EOG fuel oil system.

Select risk-significant systems are being reviewed to determine if there are any other examples of small diameter Schedule 40 piping with threaded connections subject to high-cyclic fatigue, in order to address other potential equipment configurations with vulnerabilities similar to the EOG fuel oil system. Additionally, historical Non-Conditions Adverse to Quality (NCAQ)

Condition Reports and corrective work orders, initiated per SAP-999 between February 2019 Serial No.24-022 Page 3 of 3 and February 2022, are being reviewed to identify potential unaddressed vulnerabilities or previously unidentified repetitive conditions for select risk-significant systems.

Date When Full Compliance Will be Achieved Compliance was achieved in February 2022, when SAP-999 was replaced with PI-AA-200, Corrective Action. Operability of the 'A' EOG was restored November 2, 2022, following replacement of effected fuel oil piping.